河南省不同强度降水变化及对水旱灾害的影响

利用河南省30个站点1957~2005年的逐日降水资料,计算分析了近49年来河南省不同强度降水量和降水日数的变化趋势。结合近49年的旱灾和水灾受灾面积,分析了不同强度降水对水旱灾害的影响。结果表明,近49年来,河南省暴雨日、大雨日存在弱的增加趋势,中雨日和小雨日呈现减少趋势,其中小雨日减少的线性趋势达到了0.01的显著水平。暴雨量、大雨量和中雨量都存在不显著的增加趋势,小雨量则表现显著的减少趋势,其线性趋势达到了0.05的显著水平。干旱和水灾面积都呈增加趋势,其中干旱面积增加的线性趋势通过了0.01水平上的显著性检验。不同强度的降水量和降水日数与干旱、水灾面积之间都显著相关,其中与旱灾关系最显著的是小雨量和小雨日数,而与水灾关系最显著的是暴雨量和暴雨日数。

Study on the Changes of Different Intensity Precipitation in Henan Province and Their Effects on Flood and Drought Disaster

Based on the daily precipitation data from 30 stations of Henan Province during 1957-2005,the change trend of different intensity precipitation and precipitation days in Henan Province in recent 49 years were calculated and analyzed.Combining with the disaster area of flood and drought in recent 49 years,the effects of different intensity precipitation on flood and drought were analyzed.The results showed that rainstorm days and heavy rain days in Henan Province had weakly increasing trend and moderate rain days and light rain days showed a decreasing trend.The linear trend of the decreasing light rain days had extremely significant difference at 0.01 level.Rainstorm amount,heavy rain amount and moderate rain amount had inapparent increasing trend and light rain amount showed a significant decreasing trend,with its linear trend reaching significant difference at 0.05 level.Both drought area and flood area showed the increasing trend and the linear trend of the increasing drought area passed the significant test at 0.01 level.Different intensity precipitation amount and precipitation days had significant correlation with drought and flood areas.The most significant related factors with drought were light rain amount and light rain days and that with flood were rainstorm quantity and rainstorm days.